Circular in-line air filter



FIG. 1 is a perspective view for a circular in-line air filter showing my new design;

FIG. 2 is a right side view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a front view thereof; and,

FIG. 7 is a back view thereof. 

CLAIM The ornamental design for a circular in-line air filter, as shown and described. 